Woman Starts World's Largest Exercise Class on Facebook

June 3, 2014— -- A Montana mom of eight has motivated millions of her closest friends to join her on a quest for a flatter tummy.

Robyn Mendenhall Gardner posted a 30-Day Ab Challenge on Facebook hoping to coax a few other people to join in. The likes started pouring in right away. Within a week, nearly one million people were on board with the program. Now the likes are up to 2.6 million and still climbing.

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“I can't come to everyone's home or place of work and make you do these so we all are going to have to work together to try and complete this entire challenge,” Gardner writes in somewhat of an understatement on her Facebook page.

The challenge, which started on June 1st and runs through the end of the month, consists of a series of sit-ups, crunches, leg raises and planks, all designed to strengthen the core muscles of the abs, waist and lower back. It sticks to a three day on, one day off cycle and gets progressively more challenging with each workout.

Never mind that an American Council on Exercise study found that crunches and some of the workout’s other mainstay moves rank near the bottom of the list for their ability to effectively whipping those middle muscles into shape. Cedric Bryant, the chief science officer of the Council says he thinks that exercise choice is beside the point in this case.

“There’s no arguing with the fact that the 30-day abs challenge was quite effective in mobilizing millions of individuals to get some exercise,” Bryant said.